Sheet-steel article and method of making same



July`1 1924. 1,499,985

C. W. KIRSCH SHEET STEEL ARTICLE AND METHOD 0F' MAKING SAME Filed Feb.4, 1924 Patented July l, 1924. l

UNITED STATES PATENT OFFICE.

CHARLES W. KIRSCH, `(JF STURGIS, MICHIGAN, ASSIGNQR T KIBSCH MANUFACTUR-ING COMPANY, 402E' STURGIS, MICHIGAN, A CORPORATION 0F MICHIGAN.

SHEET-STEEL ARTICLE ANDJIETHOD 0l' MAKING SAIE.

Application Med. February 4, 1924. Serial Ho. 890,516.

To all whom it may concern: articles of the same class as now produced.Be it known that I, CHARLES W. KmscH, The invention resides in themethod and a citizen of the United States, residing at producthereinafter fully described and Sturgis, in the county of St. Joseph andclaimed. State of Michigan, have invented certain In the accompanyingdrawings, I have 6o new and useful Improvements in Sheet-Steelillustrated the invention, in so far as it re- Articles and Methods ofMaking Same, of lates to the product, as embodied in curtain which thefollowing is a specification. rods as exemplar of a general class ortype This invention has for its primary object of article to whic it isadapted. to produce at less cost than heretofore cer- In said drawings:c5

tain paint-enameledsheet-steel articles pos- F 1g. 1 is a fragmentaryperspective view sessing the novel and highly advantageous of a curtainrod made in accordance with characteristics hereinafterfully set forth.the invention.

The manufacture of certain paint-enam: Fig. 2 is a section of the samemany times 16 eled sheet-metal articles such for example, enlar ed, thesection being taken on any 70 as curtain rods and articles adapted to beline ongitudinall transversely or diagorolled rather than pressed intoform, innally of Fig. 1. cludes the several ste s of first cutting aFig. 3 is a greatly enlarged fragmentary sheet of metal, either priainor lightly tinned section of rollers. employed for treating sheet 20 orcopper-plated, into stri or blanks, then metal for curtain rods, etc. 75forming or shaping said s rips; then pick- The curtain rod illustratedis of the populing the same in a chemical solution, such lar flat typeconsisting of a flat strip A of as a caustic-soda solution; then rinsingand metal having parallel overturned side drying the same; then applyinga coat of fianges B, the free edges of which are spaced i paint-enamelthereto; then baking the same,V from the middle or body-portion A topro- 80 and thereafter a plying a second coat of `vide a hollow orsubstantially tubular strucpaint enamel and) again baking the same.ture, and are spaced from each other to The invention is particularlyintended and provide a continuous open Slot C which, adapted for themanufacture of icurtain rods when the rod is positionedV for,performance and drapery hardware and will be described of its function,is disposed rearwardly of 85 in accordance with my experience in and itsthe portion A and opposes the window-casadaptation to that specific art.y in or the like.

It is desirable that curtain rods, articueference is had to my copendinapplicalarly, shall ossess the greatest possible detion for LettersPatent for meta. forming gree of rigidity consistent with low cost andmachine, filed August 9, 1923, Serial No. 90 light weight, in order thatsagging thereof 656.560, to illustrate the preferred method under theweight ofthe curtainsor draperies of forming the said rods, and asexemplary suspended therefrom, may not occur, and of means adapted forthe forming of other my invention therefore has for its primarysheet-metal articles as distinguished from 40 object to roducesheet-metal adapted for the use of dies. 95 the manutitcture of curtainrods and the This type of rod illustrated possesses a like, which willincrease the rigidity while considerable degree of rigidity and has beendecreasing the weight and costof the rods. made of open-hearthsheet-steel of a certain It is also necessary that the said rods betemper and approximating or averaging rendered absolutely rust-proof andpresent 20/1000 inch thickness, as best adapted for 100 a mostattractive appearance when finished, the purpose from the standpoint ofcost and and that the finish shall be Vvery durable. It weiglfit.V Thetemper of the metal has been is accordingly another very importantobjectV the maximum in degree permitting the formof my invention toproduce a more attracing without having the metal spring back, tivearticle possessing greater durability more or less, to an extentdetrimental to uni- 105 than heretofore and costing far less in pointformity of shape in cross-section and diffiof finish. so that the totaleconomies effected, culty in handling in the forming tools or from startto completion of the article, are devices. The temper is necessary tosuffivery appreciable, and the finished product cient rigiditylongitudinally of the rod and possesses several distinct advantages overis disadvantageous i n other respects. It is,

therefore, very desirable and advanta eous to em lloy sheet-metal whichis less e stic than t at. heretofore used and without being less rigidor of greater weight.

In carrying out my present invention, the first step consists inreducing the resiliency of the metal while increasin its hardness tothereby better adapt it to gouging, on the one hand, and increasin itsrigidity on the other.' This is effected strips of metal to be shaped orform between the rolls 1 and 2, one of said roils'having surfacerejections 3' and `constituting' a male-die e ement, andV the otherthereof having corresponding surface recesses or depressions 4 andconstituting the femaledie felement. The projections 3 have rounded orconvex crown rtions, the bases thereof meetin L the reg-)surfacepreferab? in minute fil ets 5 to engage thex'fae'e o the plate inopposition to the intervening high portions of the uw roll 9', thelatter being arranged to engage the opposite surface of the plate. Therecesses or depressions 4 of the roll 2 may and preferably do possesssharp rims or edges. The resulting sheet metal presents aat pitted faceor surface and a correspondingly uckered face or surface, both, in ointo general appearance and in dimensions of recesses or its andprojections, and close groupn of e same, resembling the coarser type `otextiles, such as towelings, for example. Pitting and puckering as shownis merely exemplary of a means for slightly increasing 'the grosscross-.sectionalv dimension, of the metal and producing `on the facesthereof minute,

closely' spaced hollows and raised portions,

re ecti'vely,V .l

ksurfaces of the rolls 1 `and 2 from which the projections 3' rise andinto which the recesses 4 are out, respectively, are c -4 lindrical soas to maintain the surfaces of t e sheet-metal between the a flatcondition. j

The action of each pair of said recesses- 4 `pits and pucl'iers in andprojections 3 of the rolls l"on the inter-- sed metal strip, issubstantially that of gawin the metal. projections are very minute andclosely grouped as above pointed out so that the surface of the stripcontaining the pits or depressions D, presents in the instanceillustrated, an appearance somewhat similar to that of an egg-shell, thede ressions being visible and tangibly appreciable. In this operationowing to the stretch of the metal of the depressed portions and thecompression of the body of the sheet between the' depressions, the metalstri becomes appreciably elongated as Well as liaving its maximumthickness, between the surface containing the depressions D and thecrowns of the projections E of the other face thereof, increased. Itsresiliency is materially dey irst-passin the The said recesses and\creased while its hardness is apparently increased. Its condition' isnow such with respect to resiliency, that it lends itself more readilyto forming and, with respect to hardness, that it imparts greaterrigidity to the rod formed therefrom.

I am thus enabled to and do use stock of somewhat greater temper thanheretofore and of approximately 18/1000 inch thickness, therebyeconomizing in original weight of raw material and gaining, in additionthereto, the amount of metal resulting from elongation. t

I preferably employ a lightly tinned stock because this can be stored ingreater quantity without rusting and further, because the non-corrosivemetal coating F indicated in Fig. 2, constitutes a permanent aid to therust-proofness of the finished product attained by the paint-enamelsurfacing. It is 4 also advantageous in respect to the adhesion of thepaint-enamel coating.

After treatment by the rolls 1 and 2 as aforesaid, and then forming, therods are ready to receive the paint-enamel surfacino without requiringthe picklin rinsing, and drying heretofore necessary, t e cost of saidoperations, the time required therefor and the space for the equipment(besides the oost of the latter) being saved. The purpose of thepickling is to chemically produce microscopic pits in the surface to robit of the smoothness inherent therein as receivedfrom the mill, it beingimpossible to secure adhesion of the paint enamel without such pitting,the latter being, however, so slight as not to be tangibly appreciableto the touch, the vnietallremaining practically as smooth to the touchas prior to the pickling but presentin a dull appearance in place of theorigina olishg The paint-ename is most commonly sprayed upon the surfaceas this is the quickest, best and `most economical. spraying thepaint-enamel on the still very smooth metal surface, a very lar epercentage of the material bounds o' into the recovery vats and it isfound that many minnte surface portions of the metal are not covered.This necessitates the application of a second coat because these minuteuncovered surface portions will soon develop rust spots. Thus, afterbaking the first coat, the second coat is applied and the bakingrepeated. Careful inspection shows that a considerable percentage of thearticles still present these minute uncovered surface portions and,because a third coat is impracticable for various reasons, thesedefective articles mhst be completely decoated and refinished at veryconsiderable cost. To eliminate this cost and obtain a ,perfectly coatedarticle by the application of only one coat of paint-enamel, isobviously of tremendous advantage and this I accomplish by the aforesaidtreatment, thereb 60st of the second coat au the labor, ,time andadditional factory space incidentA thereto.

After bein formed, the rods or other articles are ta en directly intothe paint-shop and the paint-enamel applied by means of atomizers or airbrushes, as they are sometimes called. Forcedprojection of thepaintenamel on the surface is vei7 essential to its adhesion and alsocauses a attening out of the microscopic globules so that they overlapand pile u to ei'ect complete coating. In practice, I ave found itnecessary to reduce the flow of the aint-enamel from the atomizer or airbrus to about sixty per cent of that necessary to the coating of thesmooth surfaced articles, as otherwise flooding results which miti etesagainst absolute smoothness. This is most probably due to the fact thatonly a very small percentage of the enamel bounds od' into the recoveryvats because the tangibly' appreciable unevenness or roughness of thesurface, catches and holds the enamel. The total paint, labor and spaceeconomies effected are enormous. Furthermore, most carefulinspectionvhas demonstrated conclusively that .an uncovered surfaceortion is so rare as to be ne ligible and is ogviated by the ap Iicationo a very thin second coat, either ocally or over the whole article.

It is essential that the paint-enameliused be of the type which is notbrittle when dry, and I prefer to employ that t pe which containscellulose or a vegetab e in and is, preferably, of a type that will arbaking. It is also obvious that exposed sharp metal edges will, uponapplication of pressure or friction, cut through the coating of enamelvery quickly and it is, therefore, very essential that exposed surfaces1or hi h points shall be at'or rounded instead Vof; being sharp.

The a plication of the paint-enamel by means o t e air brush or atomizeris referable to the use of hair brushes or ip ing because brushes tendto apply too muc in also saving the the recesses and too little on thehigh points,

and in dip ing, spread of t more, both the air brush. Y Y Y Theparticular pattern 'illustrated is merely exemple of a suitable and veryattractive means lfbr obtaining thedesired results, it being quiteobvious that any pattern or designthat will impart minute rounded or dathigh points devoid of sharp edges, will be equally as well adaptedto thepurpose.

From the foregoing it will be obvious that the economies in cost ofmanufacture are very comprehensive while the resultin product issuperior in point of mechanicalzexcellence and appearance to thatheretofore produced. The mechanical treatment of the metal as abovedescribed produces far better the forced contact and thin e liquid isnot obtained. Furthersaid methods are far slower thanv normally unsuitedfor results than the pickling at less cost. It is also well known thatif the rinsin following pickling, is not very thorough y accomplished,traces of the chemical remainin on the metal will `cause rust spots andpee ing of the paint-enamel.

From the foregoing it will be apparent that the invention is verycomprehensive in its mechanical aspects as re rds resultin structuralcharacteristics of tha adhesion and consequent durability of the finishand in respect to improved appearance and the several economieseffected.

Pitted and puckered as hereinbefore used and set forth in the claimsshall be construed to define not only the articular treatment orformations illustrate but any other. form` or. forms serving to reduceminute and closely grouped or space rid s and recesses possessing thecharacteristics substantially as hereinbefore defined.

claim as my invention 1. A sheet-steel article such as a channeled stripor the like made from a blank normally too resilient to be adapted forforming into said articles to adapt thelatter to maintain e product antheir shapes under loads or stresses for which they are intended, saidblank being bodily distorted to present minutely pitted and uckeredsurfaces and possessing suitably reuced resiliency and thereby ada tedfor shaping as aforesaid, to produce sai articles.

2. A Vsheet-steel article such as a channeled strip or the like madefrom a blank normally insuiiiciently rigid for forming into sucharticles to adapt the latter to maintain their shapes 'under normalloads or stresses for which they are intended, said blank bein bodilydistorted to present minutely pitted and puckered surfaces and ossessinsuitably increased rigidity and t ereby a apted for shapingY asaforesaid to produce said articles.

3. AV sheet-steel metal article such as a channeled strip or the likemade from a blank normally too resilient and insuiiciently rigid forforming into such articles to render them capable of maintaining theirnormal shapes underloads or stresses for said blank bein' l which'theyare intended. bodily distorted tol present m-inutely pitte and puckeredsurfaces and possessing suit'- ably reduced resiliency and increasedhardness and thereby adapted for shaping as aforesaid to form saidarticle.

4. A sheet-metal article such as a channeled strip or the like, madefrom a blank forming into such articles to render .them capable ofbearing loads and stresses for which they are intended withoutdistortion, said blank bodily distorted and increased in area to presentminutely pitted and puckered surfaces and thereby adapted for shaping asaforesaid into such articles.

5. A sheet-steel article such as a channeled stri or the like made :froma blank coated wit a rust-proof metal and normally unsuited for shapinginto such articles to render them capable of bearing loads and stressesfor which they are intended and .incapable of permanently retainin acoating of paint-enamel without chemica treatment before applying saidcoating, said blank 1 bodily distorted to present minutely itted andpuckered sui-faces and thereb ta apted for shaping into said articles anfor permanently retaining a coating ofY paint enamel without othertreatment.

6. A sheet-steel article such as a channeled strip or the like, madefrom a blank coated with a rust-proof metal and normally unsuited forshaping into such articles to render them capable of bearing loads andstresses for which they are intended, and incapable of permanentlyretaininga coating of paint-enamel without chemical treatment beforeapplying said coating, said blank bodily distorted and increased innormal dimension to present minute closely associated surfacedistortions and thereby adaptedifor shaping into said articles and forpermanently retaining paint-enamel without other treatment.

7. A sheet-metaly article such as a channeled strip or the like, madefrom a blank having substantially rust-proof metallic surfaces andnormally unsuited for forming into such articles to render them capableof bearing load or stress for which the same are intended and incapableof permanently retaining a. coating of paint enamel without preliminarychemical treatment, said blank bodily distorted to present minutelyclosely associated surface distortions and thereby adapted for shapinginto said articles and to permanently retain a coating of paintenamelwithout other treatment,

8. A sheet-nieta] article such as a channeled strip or the like madefrom a blank having surfaces normally incapable of permanently retaininga coating of paint enamel without preliminary chemical treatnient andnormally unsuited for forming into such articles to render them capableof bearing load or stress for which the same are intended, said blankbodily distorted to present minute. closely associated surfacedistortions and thereby adapted for shaping into said articles and forpermanently retaining a coating of paint enamel without other treatment.

9. A sheet-steel article such as a channeled strip or the like, madefrom a blank coated with a rust-proof metal and normally too resilientfor forming into said articles to render them capable of bearing loadand stress for which the same are intended and incapable of permanentlyretaining a coating of paint enamel without preliminary chemicaltreatment, said blank bodily distorted to present minute closelyassociated surface distortions and thereby suitably reduced inresiliency to adapt the saine for shapin into said articles and therebyalso adapte for permanenti retaining a. coating of paint enamel Wit outother preliminary treatment.

10. A sheet-steel article such as a channeled strip or the like madefrom a blank coated with a ustroof metal and normally insuilicientlyrigi Y for forming into such articles to render them capable of bearingload and stress for which the same are intended and incapable ofpermanently retaining a. coating of paint-enamel Without irelimmarychemical treatment, said blank odily distorted to,V resent minute,closely associated surface istortions and thereby suitably increased inrigidity to adapt the same for shaping into said articles and therebyalso adapted for permanently retaining a coating of paint enamel withoutother preliminary treatment.

1l. As a new article of manufacture, a. sheet metal channeled strip orthe like formation having throughout the extent thereof multitudinousclosely associated distortions or rearran ements of the metal forminglongitudina transverse and diagonal undulatory cross sections therein tocreate added rigidity and strength in all directions throughout theformation.

12. As a new articie of manufacture, a sheet metal channeled strip orthe like including in a part a fold or bend and having throughout thebend or folded portion thereof distortions or rearrangements of themetal constituting undulatory lines of resistance tendin to maintain theassociated parts in their nt or folded relation.

13. As a. new article of manufacture, a sheet metal channeled strip orthe like having throughout substantially the extentthereofrmultitudinous closely associated distortions or rearrangementsof the metal to normally present surface formations and create addedrigidity and strength in all directions throughout the' formation.

14. As a new article of manufacture, a channeled strip or the likeformed of sheetmetal coated with a rust-proof metal normally incapableof permanently retaining a coating of aint-enamel without preliminarychemica treatment, said strip having throughout substantially the extentthereof multitudinous closely associated distortions r rearrangements ofthe metal to create added rigidity and strength in all directionsthroughout the strip and adapted to receive and permanently retain acoating of paintenamel without preliminary chemical treatment..

15. As a new article of manufacture, a channeled strip or the likeformed of sheetsteel coated with a rust-proof metal normally incapableof permanently retaining a coating of paint-enamel without preliminarychemica treatment, said strip having throughout substantially the extentthereof multitudinous closely associated distortions or rearrangementsof the metal to create added rigidity and strength in all directionsthroughout the strip and bearing a permanent coating of paint-enamelapplied thereto without preliminary chemical treatment.

16. The method of making a shaped article, such as a channeled strip,from a metal sheet, the characteristics of which are. not well suitedfor the purpose, which consists in initially subjecting the sheet tomanipulation to distort or rearrange the normal structure thereof tonormally present surface formations and create throughout the sheet asubstantially increased rigidity while preserving substantially planefaces, then forming the sheet to produce the shape of article desired. v

17. The method of making a shaped article from a metal sheet which isnormally too flexible or resilient for the purpose for which it is to beused, which consists in initially subjecting the sheet to manipulationto distort or rearrange the normal structure thereof, thereby creatingthroughout the sheet a substantially reduced resiliency and increasedrigidity, and to present minute surface formations, then forming thesheet to produce the shape of article desired, utilizing the initialdistorting' of the structure to resist tendency to change from suchshape.

18. The method of treatin a metal sheet which is normally too flexi leor resilient for the purpose for which it is to be used, which consistsin initially subjecting the sheet to manipulation to distort orrearrange the normal structure thereof and thereby create throughout thesheet a substantially reduced resiliency and increased rigidity and topresent surface formations thereon.

19. The method of treating a metal sheet which is normally unsuited tobe readily bent and preserved in a shaped formation, which consists insubjecting the sheet to manipulation to distort oi' rearrange the:normal structure thereof and thereby create throughout the sheet asubstantially increased capability of heilig bent and maintaining ashaped condition and to present surface formations thereon.

20. The method of making a shaped article from sheet metal whichconsists in initially subjecting the sheet of metal to manipulation todistort or rearrange portions of the normal structure thereof, and topresent surface formations thereon, then bending the sheet at saidportions to produce the shaped article, utilizing the distorting ofutilizing the distorting of the sheet to assist in maintaining suchshape at the bends or folds and to create an increased rigidity`throughout the body of the sheet.

22. As a new article of manufacture, a sheet-steel article composed ofsheet-steel coated with a rust-proof metal normally incapable ofpermanently retaining a coating of paint enamel without preliminarychemical treatment, said metal presenting minute, closel associatedsurface distortions and there y adapted to permanently retain a coatingof paint enamel without preliminary chemical treatment.

23. As a new article of manufacture, a sheet-metal article composed ofat least in part a metal normally incapable of permanently retaining acoating of paint enamel without preliminary chemical treatment, saidmeta presenting minute, closely associated surface distortions andthereby adapted to permanently retain a coating of paint ename Withoutpreliminary chemical treatment.

24. As a new article of manufacture, a sheet-metal article com osed atleast in part of a metal normally incapable of permanently retaining acoating of paint enamel without preliminary chemical treatment, saidmetal presenting minute, closely associated surface distortionspresenting exposed surfaces in substantially all directions and therebyadapted to permanently retain a` coating of paint enamel withoutpreliminary chemica treatment.

25. The method of making permanently paint enameled sheet metal articleswithout chemical treatment of the surfaces thereof preliminary toapplying the paint enamel, which consists in first mechanically treatinga sheet of metal to produce minute multitudinous closely associatedsurface distortions thereof, then shaping the metal into the desiredarticle, and thereafter and without other preliminary treatment of thesurface thereof, applying a coating of paint enamel thereto.

26. The method of making permanently paint. enameled sheet metalarticles Without chemical treatment of the surfaces thereof preliminaryto applying the paint enamel, which consists in first mechanicallytreating a sheet of metal to produce minute inultitudinous closelyassociated surface distortions thereof devoid of sharp edges, thenshaping the metal into the desired article,

iso

and thereafter and without other preliminary treatment of the surfacesthereof, applying n coating of paint enamel thereto.

2T. ,The method of Yprepering sheet metal normally unsuited for shapinginto certain articles, to adapt the same for said purpose and at thesame time adapt the same to permanently retain :L coating of paintenamel Without preliminary chemical treat- 1 nient. which consists inelongating the metal and distorting the surfaces thereof to providemultiudinous minute, closely associated surface formations thereondevoid of sharp edges. Y

v n.i'ticzles, to adaptI the same for said and at 28.V The method ofpreparing sheet metal normally unsalted for shaping into certain purposethe same time adapt the same to permanentlv retain a coating of paintenamel without preliminary chemical treatment. which consists in elonating the metal and distorting the body of t e metal to providemultitudinons Y minute, closely associated surface formations thereondevoid of sharp edges, said distortion decreasing the normal resiliencyand increasing the rigidity of the metal.

CHARLES W. KIRSCH.

